Science Daily has the story:

Dr. Charles Menzel, a senior research scientist at the Language Research Center, said the design of the experiment with the "chimpanzee-as-director" created new ways to study the primate... Menzel said. "The chimpanzees used gestures to recruit the assistance of an otherwise uninformed person and to direct the person to hidden objects 10 or more meters away. Because of the openness of this paradigm, the findings illustrate the high level of intentionality chimpanzees are capable of, including their use of directional gestures. This study adds to our understanding of how well chimpanzees can remember and communicate about their environment."

Recall Dr. Michael Arbib, a theoretical neuroscientist. In 1998, he and Giacomo Rizzolatti published a paper called "Language Within Our Grasp." In that paper, Arbib and Rizzolatti presented the idea that the source of human language is in our hands. They based this idea on the scientific understanding that the part of the brain known as the language area (Broca's area) is also the neural area for processing grasping activity. Arbib and Rizzolatti concluded that the hands were used for human language long before vocal language was developed. The older language, however, is not dead; it's very much with us to this day as gestures.